This invention relates to improved slip assemblies adapted to be mounted on a well drilling rotary table for supporting a well pipe.
Copending application Ser. No. 877,309 filed Feb. 13, 1978, now abandoned, by George I. Boyadjieff et al. on "Slip Assembly" discloses a well pipe gripping slip unit which is removably positionable on the rotary table of a drilling rig to support the pipe from the rotary table when desired. The assembly of that application includes a support structure which is positionable on the rotary table and turns with it, and a carrier structure which suspends a number of pipe gripping slips and is mounted for upward and downward movement relative to the support structure between a lower active pipe gripping position and an upper retracted pipe releasing position. The carrier is retainable in its lower active position by latch means, and upon release of those latch means is urged upwardly toward the retracted position by associated yielding means. In the embodiment specifically illustrated in the drawings of that application, the lower support structure is shaped to function as a slip bowl, having wedge surfaces engageable with the slips to cam them into pipe gripping positions upon downward movement of the carrier and slips.